1. Field of the Invention
The present invention relates to a disk cartridge ideally suited for use in a large-capacity disk drive, such as a removable hard disk drive unit.
2. Description of the Related Art
FIG. 16 shows an example of a hard disk drive unit proposed by the assignee under U.S. patent application Ser. No. 09/299,498 or Japanese Unexamined Patent Application No. 11-312353. The hard disk drive unit is a removable hard disk drive unit 1 (hereinafter referred to simply as xe2x80x9cR-HDD 1xe2x80x9d) in which an upper cover 3 closes the top of a drive main body 2 having an open top, and a cartridge holder 4 is disposed at front in the drive main body 2. A cartridge insertion slot 5 is formed substantially over the full width of a front edge 4a of the cartridge holder 4. A pair of right and left hinge pins 6 are disposed at the right and left ends of a rear edge 4b of the cartridge holder 4. The front edge 4a of the cartridge holder 4 can be raised and lowered in directions indicated by arrows a and b, which are vertical in relation to the drive main body 2, about the paired right and left hinge pins 6 by a cartridge lifting device (not shown) installed at the bottom on the front edge side of the cartridge holder 4. A spindle motor 7 is disposed under the cartridge holder 4 in the drive main body 2. A chucking magnet 9 is embedded in the disk table 8 rotated together with a rotor of the spindle motor 7. Furthermore, a flexible head actuator 10, which is a rotary head actuator, is disposed at the rear of the cartridge holder 4 in the drive main body 2. The flexible head actuator 10 has a pair of upper and lower suspensions 12 mounted on the distal end of a head arm 11 by being bent at a predetermined angle, and a pair of upper and lower flying head sliders 13 mounted on the distal ends of the pair of upper and lower suspensions 12. The flexible head actuator 10 is constructed such that it is rotatably driven in longitudinal directions indicated by arrows c and d. A dynamic load and unload lamp (hereinafter referred to simply as xe2x80x9clampxe2x80x9d) 14 is disposed between the pair of upper and lower suspensions 12.
Referring now to FIG. 17, a disk cartridge 21 used with the R-HDD 1 includes a flat cartridge main body 24 formed of upper and lower halves or upper and lower shells 22 and 23, respectively, that are composed of synthetic resin moldings and vertically fastened into a one piece by screws, an adhesive agent, or the like, and a recording disk (hereinafter referred to simply as xe2x80x9cdiskxe2x80x9d) 25, which is a removable hard disk rotatably accommodated in the cartridge main body 24. A center core 26 composed of a ferromagnetic member is secured to the center of the disk 25. A head insertion slot 27, which is long sideways, is formed by the upper and lower halves 22 and 23, the slot 27 being positioned at one side of an arcuate front edge 24a of the cartridge main body 24. Substantially at the center of the lower half 23, there is a circular disk table insertion aperture 28 in which the center core 26 of the disk 25 is fitted with a play.
As indicated by the one-dot chain line in FIG. 16, with the front edge 4a of the cartridge holder 4 of the R-HDD 1 raised in the direction indicated by arrow a, the disk cartridge 21 shown in FIG. 17 is inserted aslant into the cartridge holder 4 in the direction indicated by arrow e through the cartridge insertion slot 5 from the front edge 24a of the cartridge holder 4. Thereafter, as indicated by the solid line in FIG. 16, the front edge 4a of the cartridge holder 4 is lowered in the direction indicated by arrow b to mount the cartridge holder 4 of the disk cartridge 21 on a pair of a height reference pin (not shown) and a positioning pin (not shown) located at right and left, respectively, in the drive main body 2 so as to position the cartridge holder 4. Then, the disk table 8 of the spindle motor 7 is relatively inserted from below into the disk table insertion aperture 28 of the cartridge main body 24, and the center core 26 of the disk 25 is magnetically chucked onto the disk table 8 by the chucking magnet 9.
After loading the disk cartridge 21, the disk 8 is rotatably driven at high speed by the spindle motor 7, and the flexible head actuator 10 is rotatably driven in the direction indicated by arrow c to cause the pair of upper and lower suspensions 12 to slide on the lamp 14 in the direction indicated by arrow c so as to reduce the vertical gap between the paired upper and lower suspensions 12 by the spring force of the suspensions 12 themselves. Then, the paired upper and lower suspended head sliders 13 are inserted into the head insertion slot 27 of the disk cartridge 21 from the direction indicated by arrow c to load the suspended head sliders 13 onto the upper and lower recording surfaces of the disk 25. The flexible head actuator 10 circularly moves in the directions indicated by arrows c and d to cause the pair of upper and lower suspended head sliders 13 to perform a seek in the directions indicated by arrows c and d between the inner and outer peripheries of the disk 25, thereby recording or reproducing information on or from the disk 25. After completion of recording or reproducing on or from the disk 25, the front edge 4a of the cartridge holder 4 is raised in the direction indicated by arrow a, and the disk cartridge 21 is drawn out upward aslant in the direction indicated by arrow f through the cartridge insertion slot 5, as indicated by the one-dot chain line in FIG. 16.
Using the flexible head actuator 10 as the rotary head actuator makes it possible to minimize the width of the head insertion slot 27 of the disk cartridge 21 and to achieve a simplified configuration and higher reliability of the dynamic loading and unloading device of the pair of upper and lower suspended head sliders 13, thus permitting the R-HDD 1 to have higher quality. While recording or reproducing on or from the disk 25, the pair of upper and lower suspended head sliders 13 is raised due to the airflows generated on the upper and lower recording surfaces by the high-speed rotation of the disk 25, thus recording or reproducing information in a non-contact state.
The disk cartridge 21 shown in FIG. 17 through FIG. 21 includes a plurality of rib-shaped upper partitions 29 and lower partitions 30 that are divided in the peripheral direction and arc-shaped along a rear edge 24b and right and left edges 24c and 24d, which are three edges of the cartridge main body 24, excluding the front edge 24a. The upper partitions 29 and the lower partitions 30 are formed into one piece such that they are perpendicular to vertically opposing inner surfaces 22a and 23a of the upper and lower halves 22 and 23, respectively, and are vertically symmetrical. The upper and lower halves 22 and 23 are vertically combined into one piece to vertically abut the plural upper and lower partitions, 29 and 30, respectively, thereby forming a substantially circular disk accommodation chamber 31 surrounded by these plural upper and lower partitions 29 and 30, respectively. The disk 25 is rotatably and horizontally inserted in the disk accommodation chamber 31, and the round disk table insertion aperture 28 is formed in the lower half 23, at a position corresponding substantially to the center of the disk accommodation chamber 31. In this case, a plurality of, e.g., three, dowels 32 are integrally formed on the inner surface 23a of the lower half 23 and on the outer periphery of the disk table insertion aperture 28. The center core 26 of the disk 25 is positioned by placing it on the dowels 32, and the disk 25 is horizontally supported in such a manner that it floats upward with respect to the inner surface 23a of the lower half 23.
A shutter 35 made of a thin metal plate, such as a stainless plate, is horizontally disposed on the inner surface 23a of the lower half 23, under the disk 25 so that the shutter 35 longitudinally extends in the disk accommodation chamber 31. The shutter 35 is formed by integrally pressed portions, namely, a disk table insertion aperture opening and closing portion 36 formed in a narrow, substantially fan-shaped horizontal plate, a head insertion aperture opening and closing portion 37 which is vertically bent upward at the end on the front edge of the disk table insertion aperture opening and closing portion 37 (adjacent to the front edge 24a of the cartridge main body 24) and is formed in an arc shape along the inner side of the front edge 24a of the cartridge main body 24, a proximal end portion 38 forming an end portion adjacent to a pivot that is formed near the rear edge of the disk table insertion aperture opening and closing portion 36 (adjacent to the rear edge 24b of the cartridge main body 24), a spring locking portion 39 formed on one side surface 36a of the disk table insertion aperture opening and closing portion 36 and in the vicinity of the proximal end portion 38, and an opening and closing arm 40 that is formed on the side surface 36a of the disk table insertion aperture opening and closing portion 36, extends into one side direction from a position considerably shifted toward the front edge from the proximal end portion 38, and is formed into an arc centering about a pivot pin 45 of the proximal end portion 38, which will be discussed hereinafter. A substantially central portion of the other side surface of the disk table insertion aperture opening and closing portion 36, namely, a side surface 36b, is provided with a cutout 41 serving as the relief for the disk table insertion aperture 28. Another cutout 42 serving as the relief for a filter accommodating portion 59, which will be discussed hereinafter, is formed at the position near the front edge of the side surface 36a. 
Furthermore, a spring accommodation chamber 44 is provided at the rear end of the disk accommodation chamber 31 so that it is shifted onto one side from the center of the cartridge main body 24, and is in communication with the disk accommodation chamber 31. The spring accommodation chamber 44 is formed by depressing, toward the rear (outward), a part of the upper partition 29 of the upper half 22 and the lower partition 30 of the lower half 23 constituting the outer peripheral wall of the disk accommodation chamber 31. On one side in the spring accommodation chamber 44, the proximal end portion 38 of the shutter 35 is rotatably fitted to a pivot pin 45, which serves as a pivot for circular movement, and is vertically and integrally formed on the inner surface 23a of the lower half 23, so that the shutter 35 may circularly move to the right and left, that is, in the directions indicated by arrows g and h, about the pivot pin 45. As a shutter spring, a twisted coil spring 47 having a large spring force or a spring constant is employed. A coil portion 48 of the twisted coil spring 47 is fitted and mounted from above onto the outer periphery of a boss-shaped spring retainer 46 vertically and integrally formed on the inner surface 23a of the lower half 23 on the other side in the spring accommodation chamber 44. An operating end 49 and a fixed end 50 of the twisted coil spring 47 that together form substantially a U shape, the distal end of the operating end 49 being retained by a spring retaining portion 39 of the shutter 35. The distal end of the fixed end 50 is abutted against the inner side of a recessed portion of the lower partition 30 of the lower half 23 thereby to rotatably urge the shutter 35 from an opening position shown in FIG. 20 to the closing position shown in FIG. 21 in the direction indicated by arrow g by the spring force of the operating end 49. A pair of guide slots 51 formed in the disk table insertion aperture opening and closing portion 36 of the shutter 35 and shaped like arcs around the pivot pins 45 are slidably engaged with two of the three dowels 32 integrally formed around the disk table insertion aperture 28 on the inner surface 23a of the lower half 23, thereby guiding the shutter 35 by these dowels 32. The front edge 24a of the cartridge main body 24 and the head insertion slot opening and closing portion 37 of the shutter 35 on the inner side thereof are shaped like arcs around the pivot pin 45.
The opening and closing arm 40 of the shutter 35 passes through a recessed portion 52, which is a cutout formed in a part of the lower partition 30 of the lower half 23, and juts out to one side adjacent to the rear edge 24b of the cartridge main body 24 outside the disk accommodation chamber 31. Furthermore, a distal end 40a of the opening and closing arm 40 projects outward from a slit 53 horizontally formed between the upper and lower halves 22 and 23, at the rear end of the side portion 24c of the cartridge main body 24. The distal end 40a of the opening and closing arm 40 is flexed upward from the opening and closing arm 40 by a substantially crank-shaped flexible portion 40b, then horizontally projected outward sideways from the slit 53. As described in conjunction with FIG. 16, when the disk cartridge 21 is inserted aslant in the direction indicated by arrow e into the cartridge holder 4 of the R-HDD 1 from the front edge 24a of the cartridge main body 24, the distal end 40a of the opening and closing arm 40 is relatively driven in the direction indicated by arrow f from the closing position shown in FIG. 21 to the opening position shown in FIG. 20 by a shutter opening device (not shown) provided on one side in the cartridge holder 4. This causes the shutter 35 to be circularly moved about the pivot pin 45 in the direction indicated by arrow h from the closing position shown in FIG. 21 to the opening position shown in FIG. 20 against the spring force of the operating end 49 of the twisted coil spring 47. Thus, the head insertion slot 27 and the disk table insertion aperture 28 of the cartridge main body 24 are simultaneously opened.
As explained with reference to FIG. 16, when the disk cartridge 21 is drawn out from the cartridge holder 4 of the R-HDD 1 in the direction indicated by arrow f after recording or reproducing information on or from the disk 25, the shutter 35 is automatically swung about the pivot pin 45 in the direction indicated by arrow g from the opening position shown in FIG. 20 to the closing position shown in FIG. 21 by the spring force of the operating end 49 of the twisted coil spring 47. Thus, the head insertion slot 27 and the disk table insertion aperture 28 of the cartridge main body 24 are automatically closed by the head insertion slot opening and closing portion 37 and the disk table insertion aperture opening and closing portion 36 of the shutter 35.
In the vicinity of the right and left corners of the lower half 23, at the rear edge 24b of the cartridge main body 24, a pair of right and left boss-shaped positioning protuberances 57 and 56, respectively, are integrally formed. The right protuberance 57 has an oval positioning aperture 55 opened therein, while the protuberance 56 has a round positioning aperture 54 opened therein. As explained in conjunction with FIG. 16, when the disk cartridge 21 is loaded in the direction indicated by arrow b by the cartridge holder 4, the pair of right and left positioning apertures 55 and 54 of the disk cartridge 21 are fitted from above onto a pair of right left positioning pins (not shown) provided in the drive main body 2 of the R-HDD 1, thereby positioning the disk cartridge 21 in the drive main body 2. Furthermore, in the lower half 23, a write protector 58 for preventing erroneous deletion of information from the disk 25 is installed on the inner side from the positioning protuberance 56 such that the write protector 58 may laterally slide. At the front edge 24a of the cartridge main body 24, in the corner area located on the opposite side from the head insertion slot 27, a substantially arcuate filter accommodation chamber 59 is formed at a position outside the disk accommodation chamber 31. The filter accommodation chamber 59 is defined by a part of the upper and lower partitions 29 and 30 of the upper and lower halves 22 and 23. Both arcuate ends of the filter accommodation chamber 59 are in communication with the disk accommodation chamber 31, and a circulation filter 60 is detachably installed in the filter accommodation chamber 59. At the time of recording or reproducing on or from the disk 25, the airflow generated when the disk 25 rotates at high speed in the disk accommodation chamber 31 is repeatedly circulated in the disk accommodation chamber 31, the spring accommodation chamber 44, and the filter accommodation chamber 59 so as to cause dust in the disk cartridge 21 to be adsorbed by the circulation filter 60, thereby collecting dust. Thus, air in the disk cartridge 21 is purified.
In the disk cartridge 21 described above, the spring accommodation chamber 44 formed by denting a part of the outer peripheral wall of the disk accommodation chamber 31 is in communication with the disk accommodation chamber 31.
According to the construction set forth above, however, the spring accommodation chamber 44 is formed by denting outward a part of the outer peripheral wall of the disk accommodation chamber 31, and a part of the outer peripheral wall of the disk accommodation chamber 31 is cut off. Hence, an airflow that is produced when the disk 25 is rotated at high speed in the disk accommodation chamber 31, and moves along the upper and lower partitions 29 and 30 constituting the outer peripheral wall of the disk accommodation chamber 31 may be disturbed in the spring accommodation chamber 44 formed of outward dent. As a result, there is a danger in that smooth airflow may be prevented in the disk accommodation chamber 31, and the efficiency of airflow circulation in relation to the circulation filter 60 may be deteriorated, resulting in deteriorated dust collecting efficiency of the circulation filter 60.
As the type of the disk cartridge previously applied by the assignee, there is one disclosed in, for example, U.S. Pat. No. 5,949,630, wherein the disk accommodation chamber of a cartridge is provided with a partitioning member for providing a partition in the direction in which a pair of shells constituting the cartridge overlap, and a twisted coil spring is accommodated, via the partitioning members, in the direction for overlapping the disk. In this construction, however, the disk, the partitioning member, and the twisted coil spring inevitably overlap in the axial direction of the disk, making it difficult to reduce the thickness of the cartridge.
The present invention has been made with a view toward solving the problems described above, and it is an object of the present invention to provide a disk cartridge that is thinner and capable of significantly improving the circulation efficiency of airflow in a disk accommodation chamber and the efficiency of dust collection, and also permits a reduction in the required spring force of a shutter spring that rotatably urges a shutter in the direction for closing.
To this end, according to one aspect of the present invention, there is provided a disk cartridge characterized in that a spring accommodation chamber separated by a partition is formed outside a disk accommodation chamber in a cartridge body, and a shutter spring for rotatably urging a shutter in a direction for closing is housed in the spring accommodation chamber.
In the disk cartridge in accordance with the present invention constructed as described above, the shutter spring for rotatably urging the shutter in the direction for closing is housed in the spring accommodation chamber that is located outside the disk accommodation chamber and separated by the partition. This arrangement restrains inflow or outflow of air between the disk accommodation chamber and the spring accommodation chamber, so that an airflow in the disk accommodation chamber will not be disturbed, thus ensuring smooth airflows.